views: add focus ring to TreeView

ui/views/controls/tree/tree_view.cc

Index: ui/views/controls/tree/tree_view.cc
diff --git a/ui/views/controls/tree/tree_view.cc b/ui/views/controls/tree/tree_view.cc
index a87875e7870ddb7af5c099fcd3f9a917d7d549a1..42a34bf4ab09608e4cb5c22578199d3a0d7c447b 100644
--- a/ui/views/controls/tree/tree_view.cc
+++ b/ui/views/controls/tree/tree_view.cc
@@ -11,6 +11,7 @@
 #include "base/message_loop/message_loop.h"
 #include "ui/accessibility/ax_view_state.h"
 #include "ui/base/ime/input_method.h"
+#include "ui/base/material_design/material_design_controller.h"
 #include "ui/base/resource/resource_bundle.h"
 #include "ui/events/event.h"
 #include "ui/events/keycodes/keyboard_codes.h"
@@ -21,6 +22,7 @@
 #include "ui/gfx/skia_util.h"
 #include "ui/native_theme/native_theme.h"
 #include "ui/resources/grit/ui_resources.h"
+#include "ui/views/controls/focus_ring.h"
 #include "ui/views/controls/prefix_selector.h"
 #include "ui/views/controls/scroll_view.h"
 #include "ui/views/controls/textfield/textfield.h"
@@ -631,6 +633,12 @@ void TreeView::OnFocus() {
   // Notify the InputMethod so that it knows to query the TextInputClient.
   if (GetInputMethod())
     GetInputMethod()->OnCaretBoundsChanged(GetPrefixSelector());
+
+  if (ui::MaterialDesignController::IsSecondaryUiMaterial()) {
+    View* focus_ring_view = FindFocusRingView();
+    FocusRing::Install(focus_ring_view);
+    focus_ring_view->SchedulePaint();
+  }
 }
 
 void TreeView::OnBlur() {
@@ -639,6 +647,11 @@ void TreeView::OnBlur() {
   SchedulePaintForNode(selected_node_);
   if (selector_)
     selector_->OnViewBlur();
+  if (ui::MaterialDesignController::IsSecondaryUiMaterial()) {
+    View* focus_ring_view = FindFocusRingView();
+    FocusRing::Uninstall(focus_ring_view);
+    focus_ring_view->SchedulePaint();
+  }
 }
 
 bool TreeView::OnClickOrTap(const ui::LocatedEvent& event) {
@@ -1057,6 +1070,20 @@ bool TreeView::IsPointInExpandControl(InternalNode* node,
   return arrow_bounds.Contains(point);
 }
 
+View* TreeView::FindFocusRingView() {
+  // If this View is the grandchild of a ScrollView, use the grandparent
+  // ScrollView for the focus ring instead of this View so that the focus ring
+  // won't be scrolled. Otherwise, fall back to using this View. Since
+  // ScrollViews have a single content view, which they wrap in a
+  // ScrollView::Viewport, being the grandchild of a ScrollView implies being
+  // the sole grandchild, which means it's fine to wrap the focus ring around
+  // the grandparent here.
+  View* grandparent = parent() ? parent()->parent() : nullptr;
+  if (grandparent && grandparent->GetClassName() == ScrollView::kViewClassName)

[sky, 2016/10/11 18:17:15]

Did you verify we want this behavior everywhere? On other platforms its more
common to draw focus around the selected row(s), not the whole container. For
mac, do the indicators typically extend around the scrollbars too? I would
expect it to stay in the viewport, but then I haven't paid close attention to
the behavior on a mac.

+    return grandparent;
+  return this;
+}
+
 // InternalNode ----------------------------------------------------------------
 
 TreeView::InternalNode::InternalNode()